4 ms·

I believe DX in this context means "long distance".

• Enginerrrd 4y ago
  Yeah, more specifically, it usually is referring to radio signal propagating using some form of bounce off the ionosphere. Usually only relatively lower frequencies do this (these are unfortunately named "HF" for high frequency). The more the earth is bombarded by charged particles, the less transparent the ionosphere is to radio signals, so the more likely you are to get a bounce from higher frequencies.